WHEN Roland Fryer was about 15, a friend asked him what he would be doing when he was 30. He said he would probably be dead. It was a reasonable prediction. At the time, he was hanging out with a gang and selling drugs on the side. Young black men in that line of work seldom live long. But Mr Fryer survived. At 30, he won tenure as an economics professor at Harvard. That was four months ago.
